The present invention relates to an audio signal processing apparatus, and more particularly, to an apparatus and method for processing an audio signal according to surround modes, in which a surround-sound of an original sound timbre can be reproduced in accordance with a particular surround mode by carrying surround code information with the audio signal being transmitted, and by detecting the surround code information upon receipt of the audio signal.
In general, many audio apparatuses which have a surround circuit capable of producing the surround-sound of a current sound, i.e. a feeling of a sound field where an original sound timbre is produced for a listener, are installed have become popular. Unlike a stereo system, a surround-sound system is capable of reproducing a feeling of a sound field by generating an inherent reflected sound responsive to an audio signal.
FIG. 1 shows an audio apparatus in which the surround circuit is installed, which is disclosed in Korean patent application 92-7759 filed by the applicant of the present invention. A surround unit 14 has a plurality of surround circuits 14a, 14b, and 14c which delay the audio signal applied from the left and right audio input terminals L and R, in order to represent different surround-sound effects. A switch 16 connects one of the surround circuits 14a, 14b, or 14c to left and right surround exclusive speakers SSP1 and SSP2. A controller 18, for example, a microcomputer, controls the switch 16. A sound adjuster 10 adjusts a base, balance, treble, and volume of the audio signal, and then outputs the adjusted audio signal through speakers SP1 and SP2. An amplifier 12, connected to output terminals of the sound adjustor 10, amplifies the audio signal supplied to the speakers SP1 and SP2.
The audio apparatus shown in FIG. 1 can advantageously provide a variable surround-sound effect to a user by having a plurality of surround circuits installed in which each surround circuit generates a surround-sound effect that is different from the others.
However, the audio apparatus shown in FIG. 1 is inconvenient to use. This is because the surround circuits which generate a surround-sound effect corresponding to a particular surround-sound characteristic, such as a sound produced in a studio, concert hall, playground, theater, etc., should be individually selected by a user in accordance with the desired surround-sound characteristic.
Moreover, when the surround-sound characteristic of the desired surround circuit selected by the user does not match the surround-sound characteristic of the desired original sound, the desired surround-sound effect can not be fully generated.